X-Pack monitoring gives you insight into the operation of Elasticsearch, Logstash, and Kibana. All of the monitoring metrics are stored in Elasticsearch, which enables you to easily visualize the data from Kibana. From the Kibana Monitoring UI, you can spot issues at a glance and delve into the system behavior over time to diagnose operational issues. In addition to the built-in status warnings, you can set up custom alerts based on the data in the monitoring indices.
For more information, see: